This code:

$query = Doctrine_Query::create()
    ->from('User u')
    ->leftJoin('u.Roles')   // join "to many"
    ->orderBy('u.id');    // using primary key
$pager = new Doctrine_Pager($query, $page, $perPage);
$records = $query->execute();

raises an exception "ambigous column 'id'":

Doctrine_Connection_Pgsql_Exception: SQLSTATE[42702]: Ambiguous column: 7 ERROR: ссылка на колонку "id" неоднозначна LINE 1: ..."."id" = "r2"."role_id" WHERE "u"."id" IN (SELECT "doctrine_... ^{in /home/common/library/Doctrine/Connection.php on line 1076}

because there are two links to one column in autogenerated SQL:

SELECT ... FROM "user" "u" LEFT JOIN "role-user" "r2" ON "u"."id" = "r2"."user_id" LEFT JOIN "role" "r" ON "r"."id" = "r2"."role_id" WHERE "u"."id" IN (SELECT "doctrine_subquery_alias"."id" FROM (SELECT DISTINCT "u2"."id", "u2"."id" FROM "user" "u2" LEFT JOIN "role-user" "r4" ON "u2"."id" = "r4"."user_id" LEFT JOIN "role" "r3" ON "r3"."id" = "r4"."role_id" ORDER BY "u2"."id" LIMIT 3) AS doctrine_subquery_alias) ORDER BY "u"."id"